package com.kfm.pm;

public class Demo01 {

    public static void main(String[] args) {
        //
        Integer i = new Integer(9);
        System.out.println(i);
        // 将数字字符串转换成 Double类型
        Double d = new Double("23.3");
        System.out.println(d);
        // 将基本数据类型double转换成Double类型
        Double d2 = new Double(23.3);
        System.out.println(d == d2);
        System.out.println(Integer.MAX_VALUE);
        System.out.println(Integer.MIN_VALUE);
        System.out.println(Character.MIN_VALUE);
        System.out.println(Character.MAX_VALUE);
        System.out.println(Double.MIN_VALUE);

        // int --> Integer 装箱
        int a = 1;
        Integer b = Integer.valueOf(a);
        // double --> Double
        double d5 = 23.3;
        Double d6 = Double.valueOf(d5);

        // Double --> double 拆箱
        Double d3 = new Double(23.3);
        double d4 = d3.doubleValue();

    }
}
